This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A043271 #4 Mar 30 2012 18:56:34 %S A043271 0,1,2,3,4,5,6,7,8,9,10,11,2,4,6,8,10,12,14,16,18,20,22,2,3,4,5,6,7,8, %T A043271 9,10,11,12,13,4,5,6,7,8,9,10,11,12,13,14,15,6,7,8,9,10,11,12,13,14, %U A043271 15,16,17,8,9,10,11,12,13,14,15,16,17,18,19,10 %N A043271 Sum of the digits of the n-th base 12 palindrome. %Y A043271 A029957 (base 12 palindromes) %K A043271 nonn,base %O A043271 1,3 %A A043271 _Clark Kimberling_